Lighting Requirements Calculator
Calculate the required lumen output and LED bulb options based on room type and area.
Choose the Right Lighting for Every Room
Too little light causes eye strain and mistakes, while excessive lighting means wasted energy and loss of comfort. To calculate the right amount of lighting you only need the room type and area. Based on EN 12464-1 and IESNA standards, this tool calculates the lux value per square metre and the total lumen requirement, then lists LED bulb options at different wattages.
What Is the Difference Between Lumen and Lux?
Lumen (lm) is the total amount of light emitted by a source — think of it as the bulb's "brightness power". Lux (lx) is the amount of light falling on a unit area (1 m²): 1 lux = 1 lumen / m². Divide the number of lumens a bulb emits by the room area to find the lux value.
Standard Lux Values by Room Type
| Room Type | Recommended Lux | Reason |
|---|---|---|
| Living Room | 100–300 lux | Comfortable reading and social activity |
| Bedroom | 100–200 lux | Calm, low light; supports sleep quality |
| Kitchen | 300–500 lux | High visibility for cutting and cooking |
| Study / Office | 500–750 lux | Extended screen or paperwork sessions |
| Bathroom | 250–500 lux | Safe movement and personal care |
| Hallway / Corridor | 80–150 lux | Sufficient orientation for a transit area |
| Garage | 150–300 lux | Vehicle maintenance and safety |
How to Choose LED Bulbs
Watt ≠ Brightness
With old incandescent bulbs the wattage indicated brightness. For LED bulbs, look at the lumen value; wattage only indicates energy consumption. For example an 8 W LED can produce the same brightness as a 60 W incandescent (≈806 lm).
Colour Temperature
2700–3000 K (Warm White) — relaxing for living rooms and bedrooms.
4000 K (Neutral White) — practical for kitchens and bathrooms.
5000–6500 K (Cool White) — high contrast for studies and garages.
Light Distribution and Fixtures
Placement is just as important as the number of bulbs. Distributing several medium-power bulbs rather than a single powerful one spreads light more evenly and reduces shadow spots. Spotlights, panels and pendant fixtures have different beam angles.
Key Considerations in Lighting Design
- As ceiling height increases, lighting efficiency decreases; for ceilings above 3 metres, increase the lumen requirement by 20–30%.
- Dark-coloured walls and floors absorb light; fewer bulbs are needed with light-coloured surfaces.
- Add task lighting for areas such as a work desk or kitchen counter; don't rely solely on general lighting.
- If you can use a dimmer, you gain more flexible lighting control rather than relying on a single fixed-power bulb.